tcp: misc cleanup of options for rack as well as socket option logging.

Both BBR and Rack have the ability to log socket options, which is currently disabled. Rack
has an experimental SaD (Sack Attack Detection) algorithm that should be made available. Also
there is a t_maxpeak_rate that needs to be removed (its un-used).

Reviewed by: tuexen, cc
Sponsored by: Netflix Inc
Differential Revision: https://reviews.freebsd.org/D39427

sys/conf/options

@@ -229,6 +229,12 @@ SW_WATCHDOG	opt_watchdog.h
 TCPHPTS         opt_inet.h
 TCP_REQUEST_TRK opt_global.h
 TCP_ACCOUNTING	opt_inet.h
+#
+# TCP SaD Detection is an experimental Sack attack Detection (SaD)
+# algorithm that uses "normal" behaviour with SACK's to detect
+# a possible attack. It is strictly experimental at this point.
+#
+TCP_SAD_DETECTION opt_inet.h
 TURNSTILE_PROFILING
 UMTX_PROFILING
 UMTX_CHAINS	opt_global.h

sys/netinet/tcp.h

@@ -424,6 +424,9 @@ struct tcp_info {
 	u_int32_t	__tcpi_received_e0_bytes;
 	u_int32_t	__tcpi_received_ce_bytes;
 
+	u_int32_t	tcpi_total_tlp;		/* tail loss probes sent */
+	u_int64_t	tcpi_total_tlp_bytes;	/* tail loss probe bytes sent */
+
 	/* Padding to grow without breaking ABI. */
 	u_int32_t	__tcpi_pad[19];		/* Padding. */
 };

sys/netinet/tcp_log_buf.h

@@ -255,7 +255,7 @@ enum tcp_log_events {
 	TCP_LOG_CONNEND,	/* End of connection                54 */
 	TCP_LOG_LRO,		/* LRO entry                        55 */
 	TCP_SACK_FILTER_RES,	/* Results of SACK Filter           56 */
-	TCP_SAD_DETECTION,	/* Sack Attack Detection            57 */
+	TCP_SAD_DETECT,		/* Sack Attack Detection            57 */
 	TCP_TIMELY_WORK,	/* Logs regarding Timely CC tweaks  58 */
 	TCP_LOG_USER_EVENT,	/* User space event data            59 */
 	TCP_LOG_SENDFILE,	/* sendfile() logging for TCP connections 60 */

sys/netinet/tcp_stacks/bbr.c

@@ -2991,13 +2991,6 @@ __bbr_get_bw(struct tcp_bbr *bbr)
 		bw = bbr->r_ctl.red_bw;
 	else
 		bw = get_filter_value(&bbr->r_ctl.rc_delrate);
-	if (bbr->rc_tp->t_peakrate_thr && (bbr->rc_use_google == 0)) {
-		/*
-		 * Enforce user set rate limit, keep in mind that
-		 * t_peakrate_thr is in B/s already
-		 */
-		bw = uqmin((uint64_t)bbr->rc_tp->t_peakrate_thr, bw);
-	}
 	if (bw == 0) {
 		/* We should not be at 0, go to the initial window then  */
 		goto use_initial_window;
@@ -10071,9 +10064,6 @@ bbr_init(struct tcpcb *tp, void **ptr)
 	bbr->r_ctl.rc_initial_hptsi_bw = bbr_initial_bw_bps;
 	if (bbr_resends_use_tso)
 		bbr->rc_resends_use_tso = 1;
-#ifdef NETFLIX_PEAKRATE
-	tp->t_peakrate_thr = tp->t_maxpeakrate;
-#endif
 	if (tp->snd_una != tp->snd_max) {
 		/* Create a send map for the current outstanding data */
 		struct bbr_sendmap *rsm;
@@ -11668,20 +11658,10 @@ bbr_what_can_we_send(struct tcpcb *tp, struct tcp_bbr *bbr, uint32_t sendwin,
 	return (len);
 }
 
-static inline void
-bbr_do_error_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error)
-{
-#ifdef NETFLIX_STATS
-	KMOD_TCPSTAT_INC(tcps_sndpack_error);
-	KMOD_TCPSTAT_ADD(tcps_sndbyte_error, len);
-#endif
-}
-
 static inline void
 bbr_do_send_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap *rsm, int32_t len, int32_t error)
 {
 	if (error) {
-		bbr_do_error_accounting(tp, bbr, rsm, len, error);
 		return;
 	}
 	if (rsm) {
@@ -11690,10 +11670,8 @@ bbr_do_send_accounting(struct tcpcb *tp, struct tcp_bbr *bbr, struct bbr_sendmap
 			 * TLP should not count in retran count, but in its
 			 * own bin
 			 */
-#ifdef NETFLIX_STATS
 			KMOD_TCPSTAT_INC(tcps_tlpresends);
 			KMOD_TCPSTAT_ADD(tcps_tlpresend_bytes, len);
-#endif
 		} else {
 			/* Retransmit */
 			tp->t_sndrexmitpack++;
@@ -14206,9 +14184,6 @@ bbr_set_sockopt(struct inpcb *inp, struct sockopt *sopt)
 	case TCP_BBR_PACE_SEG_MIN:
 	case TCP_BBR_PACE_CROSS:
 	case TCP_BBR_PACE_OH:
-#ifdef NETFLIX_PEAKRATE
-	case TCP_MAXPEAKRATE:
-#endif
 	case TCP_BBR_TMR_PACE_OH:
 	case TCP_BBR_RACK_RTT_USE:
 	case TCP_BBR_RETRAN_WTSO:
@@ -14474,14 +14449,7 @@ bbr_set_sockopt(struct inpcb *inp, struct sockopt *sopt)
 		BBR_OPTS_INC(tcp_rack_pkt_delay);
 		bbr->r_ctl.rc_pkt_delay = optval;
 		break;
-#ifdef NETFLIX_PEAKRATE
-	case TCP_MAXPEAKRATE:
-		BBR_OPTS_INC(tcp_maxpeak);
-		error = tcp_set_maxpeakrate(tp, optval);
-		if (!error)
-			tp->t_peakrate_thr = tp->t_maxpeakrate;
-		break;
-#endif
+
 	case TCP_BBR_RETRAN_WTSO:
 		BBR_OPTS_INC(tcp_retran_wtso);
 		if (optval)
@@ -14553,9 +14521,7 @@ bbr_set_sockopt(struct inpcb *inp, struct sockopt *sopt)
 		return (tcp_default_ctloutput(inp, sopt));
 		break;
 	}
-#ifdef NETFLIX_STATS
 	tcp_log_socket_option(tp, sopt->sopt_name, optval, error);
-#endif
 	INP_WUNLOCK(inp);
 	return (error);
 }